Total Serum IgE Levels in Asthmatic Children

Rationale: Total serum IgE levels (sIgE) are elevated in allergic diseases and correlate with asthma severity in children. The objective is to determine sIgE in asthmatic patients and associate to clinical characteristics.

Methods: This is a retrospective analysis of 1664 asthmatic patients; 189 were excluded due to other conditions that might interfere in sIgE, such as helminthiasis (n=1475). Skin prick tests (SPT) with standardized extracts of 11 allergens, FDA Allergenics® , were obtained in 663 patients. Tests were considered positive if wheal diameter was ≥ 3mm. Total serum IgE was determined by chemiluminescence. Asthma diagnosis and severity classified according to GINA 2014.

Results: 891 (60.4%) were male, median age 5.6 years (0.2 – 20 years); 86.8% had allergic rhinitis, 8% atopic dermatitis and 20.7% allergic conjunctivitis. 12.4% had no allergy-related comorbidities. Asthma was considered mild to moderate in 1165 (78.9%) and severe in 310 (21.1%). 362 (54.6%) had positive skin prick tests: 89.8% D. pteronyssinus; 70.7% B. tropicalis; 14.4% Lolium perenne; 8% B. germanica; 15.2% dog epithelium and 5.5% cat epithelium. There was a linear relationship between age and sIgE (p<0.001). The sIgE was similar in both mild to moderate and severe groups (p=0.72). Subjects with positive SPT had higher sIgE (p=0.004). Patients with severe asthma had more eosinophilia (p=0.001) and those with conjunctivitis had higher sIgE.

Conclusions:  sIgE did not correlate with asthma severity and increased with age in this group.